The present invention provides an improved coupling guard for enclosing a rotating shaft or other device to prevent access during operation and to prevent leakage of lubricant during operation. The coupling guard is easy to assemble and disassemble, and it eliminates the need for bolts, wrenches and specially sized O-ring seals in assembling the guard.
Various devices are known for covering or protecting a rotating shaft or coupling. Some examples are disclosed in U.S. Pat. Nos. 1,153,467; 1,012,909; and 600,375. These references disclose a cylindrical covering formed from one or two cylindrical shell portions with the portions being fastened together by using screws, bolts or rivets. Such fastening devices make it difficult and cumbersome to remove the cover for service to the coupling. It is desirable to have a coupling guard that may be easily and quickly assembled and disassembled to allow for convenient and easy access to the coupling for maintenance and inspection. It is further desirable to have a coupling guard that is capable of wholly enclosing the coupling, rotating shaft or other moving mechanical device in order to prevent access during operation and to provide for the safety of those working nearby. It is also desirable to have a coupling guard that is substantially leakproof so that oils may be used to lubricate the coupling or rotating shafts while in use without a concern for leaking oil.
Various fittings, flanges, latches and joints for joining cylindrical portions are known in the art. Representative examples are shown in U.S. Pat. Nos. 136,755; 1,199,496; 1,948,232; 3,425,456; and 4,128,160. In U.S. Pat. No. 4,128,160, Deal et al. disclose a leak free housing for encasing a vertical screw conveyor comprising two C-shaped cylindrical half portions assembled by means of a novel joint structure. The joint consists of hook-like flanges that seal as one flange fits inside the other. A clamp is provided to maintain a tight seal between the two portions. The disclosure states that gaskets are unworkable because the device is intended to be used with foodstuffs.
As known in the art, various types of rivets and bolts are commonly used to fasten cylindrical portions together in forming coupling guards. These rivets or bolts must be "popped" or undone in order to gain access to the coupling or shaft inside the guard and must be replaced in reassembling the guard. In addition, the prior art devices typically utilize specially sized O-ring seals in order to seal the guard against leakage. None of the devices known in the art, however, are capable of providing a leakproof enclosure that is readily assembled and disassembled without the use of rivets or bolts. The present invention provides such a coupling guard and includes a coupling mechanism that differs from the prior art in its unique configuration and the use of a resilient seal.